# Is there any effective way to solve cubic equation?

I need to solve some cubic equations, but we didn't study how to do so. So, please can you provide a tip in order to solve cubic equations. Without factoring it, because it's not all the time e=0. I want something like b^2-4ac for square equations. Ex: $x^2-x-2=0$

1. Step1: we could do some factoring like $(x-1)(x+2)=0$
Step2: then $x=1$ or $x=-2$ that's it.
2. Step1: $b^2-4ac = 1-4(1)(-2) = 9$
Step2: $x_1 = \frac{1-\sqrt9}2 = -4/2 = -2$ or $x_2= \frac{1+\sqrt9}2 = 2/2 = 1$

In short, I wanna something like the second one not the first, something automatically gives you the answer.

• google "roots of cubic equations" Commented Sep 23, 2015 at 11:06
• Google it as he said and please write in latex, it is unreadable as iti s now. Commented Sep 23, 2015 at 11:06
• @ZelosMalum, could you kindly refrain from biting the newcomers like that? It's perfectly clear which formulas he intends to write, and if you want them to look prettier, you can suggest an edit to TeXify them yourself. Commented Sep 23, 2015 at 11:10
• @uniquesolution I did, I found in wiki how to find Delta. Yet, I didn't find how to find the exact roots Commented Sep 23, 2015 at 11:11
• @AmineMarzouki: What most of us do is to code the formulas in MathJax (or LaTeX) format on a regular keyboard. See this tutorial on Meta for help on how to format various kinds of formulas -- but for a basic start, you can just enclose "ASCII math" in dollar signs: writing $x^2-x-2=0$ produces $x^2-x-2=0$. Commented Sep 23, 2015 at 11:20